{
  "height": 71,
  "block_hash": "35b8ce208d809f5793c26d9663a874b16b31795cad7000ba6f90311dc805eedf",
  "status": "confirmed",
  "bitcoin_block_height": 974880,
  "digest": {
    "alg": "sha256",
    "hex": "35b8ce208d809f5793c26d9663a874b16b31795cad7000ba6f90311dc805eedf",
    "preimage": "block:{\"at\":\"2026-11-07T02:02:15.213Z\",\"entry_count\":1,\"first_seq\":165,\"height\":71,\"key_id\":\"key_a521921c2ba20669\",\"last_seq\":165,\"merkle_root\":\"37a9e830cb046d108aedefebcf6c42ad8ef3638ca58a04bada71442d596b1009\",\"prev_hash\":\"4b2960e5f02552ac5b72c8c5d2f9192be4b3f3809c42d5addc926c416bd499c5\",\"v\":1}"
  },
  "calendars": [
    {
      "calendar": "https://a.pool.opentimestamps.org",
      "status": "confirmed",
      "submitted_at": "2026-11-07T02:08:43.462Z",
      "updated_at": "2026-11-07T04:08:43.478Z",
      "bitcoin_block_height": 974880,
      "attestations": [
        {
          "type": "pending",
          "uri": "https://alice.btc.calendar.opentimestamps.org",
          "commitment": "6aee882dd6c956c4fb82e80a31de4bc6483caf2e4ce0bf3b9d64bb7035023dfe06c368229bd98b1fcfe92372"
        },
        {
          "type": "bitcoin",
          "block_height": 974880,
          "merkle_root": "e20917e92c25ba0bebbc60b5b7fe48f0ee84f05c3eb4987c3107d249f2c7113d"
        }
      ]
    },
    {
      "calendar": "https://b.pool.opentimestamps.org",
      "status": "confirmed",
      "submitted_at": "2026-11-07T02:08:43.462Z",
      "updated_at": "2026-11-07T04:08:43.478Z",
      "bitcoin_block_height": 974883,
      "attestations": [
        {
          "type": "pending",
          "uri": "https://bob.btc.calendar.opentimestamps.org",
          "commitment": "6aee882d47b8ff8150565b42d7792f39e039cdd603a2a72e1652b26c11c51e9b4419718e3f27c041cd328130"
        },
        {
          "type": "bitcoin",
          "block_height": 974883,
          "merkle_root": "79abb9dd33baad0a1ff37045cc779f6fe1b133a7037999fbd2c996ad78e43b90"
        }
      ]
    },
    {
      "calendar": "https://finney.calendar.eternitywall.com",
      "status": "pending",
      "submitted_at": "2026-11-07T02:08:43.462Z",
      "updated_at": "2026-11-07T02:08:43.462Z",
      "bitcoin_block_height": null,
      "attestations": [
        {
          "type": "pending",
          "uri": "https://finney.calendar.eternitywall.com",
          "commitment": "6aee882dc9a0dac93955ff17c51f8f7229babe5743f89683f6813fb3e21de869dfbe1683deda16b01a7508bc"
        }
      ]
    }
  ],
  "proof_url": "https://www.a2ally.com/v1/ledger/blocks/71/anchor.ots",
  "how_to_verify": "Download the .ots proof and run `ots verify -d <block_hash> <file>.ots` with the OpenTimestamps client, which checks the Bitcoin attestation against Bitcoin block headers. The digest is the block hash: sha256 of digest.preimage, the text \"block:\" followed by the canonical block header, which is the same header the issuer signs."
}